Packaged sensor with multiple sensors elements
The present disclose relates to sensor including multiple sensor elements. In some cases, the multiple sensor elements may be mounted on a single substrate and each may be configured to sense a single parameter with different resolutions, sensitivities, and/or ranges, and/or the multiple parameters. In one example, multiple pressure sensing die may be mounted in a single package, and each may be configured as a differential pressure sensor, an absolute pressure sensor, and/or a gauge pressure sensor, as desired.
1. A pressure sensor comprising:
a substrate including a first side and a second side;
a first pressure sensing die mounted on the first side of the substrate, wherein the first pressure sensing die includes a diaphragm and one or more piezoresistive elements positioned on the diaphragm, wherein the first pressure sensing die is positioned over a first opening in the substrate, the first opening extending between the first side and the second side of the substrate;
a second pressure sensing die mounted on the first side of the substrate, wherein the second pressure sensing die includes a diaphragm and one or more piezoresistive elements positioned on the diaphragm;
a first housing member positioned on the first side of the substrate and defining a first cavity around the first pressure sensing die and the second pressure sensing die, wherein the first housing member includes a first pressure opening for exposing the first pressure sensing die and/or the second pressure sensing die to a first pressure; and
a second housing member positioned on the second side of the substrate and defining a second cavity, wherein the second housing member includes a second pressure opening for exposing the first pressure sensing die and/or the second pressure sensing die to a second pressure.
2. The pressure sensor of claim 1 , wherein the second pressure sensing die is positioned over a second opening in the substrate, the second opening extending between the first side and the second side of the substrate.
3. The pressure sensor of claim 2 , wherein the first pressure sensing die is configured to provide a first resolution of a sensed pressure and the second pressure sensing die is configured to provide a second resolution of the sensed pressure, wherein the first resolution is higher than the second resolution.
4. The pressure sensor of claim 3 , wherein the first pressure sensing die is configured to provide the first resolution of the sensed pressure over a first range and the second pressure sensing die is configured to provide the second resolution of the sensed pressure over a second range, wherein the first range is smaller than the second range.
5. The pressure sensor of claim 1 , wherein the first housing member includes a third pressure opening and a wall defining a first chamber and a second chamber, wherein the first chamber houses the first pressure sensing die and is exposed to the first pressure opening and the second chamber houses the second pressure sensing die and is exposed to the third pressure opening.
6. The pressure sensor of claim 5 , wherein the third pressure opening is exposed to atmosphere and the second pressure sensing die is an absolute pressure sensing die configured to measure barometric pressure.
7. The pressure sensor of claim 5 , wherein the second pressure sensing die is positioned over a second opening in the substrate, the second opening extending between the first side and the second side of the substrate, wherein the third pressure opening is exposed to atmosphere and the second pressure sensing die is a gauge pressure sensing die.
8. The pressure sensor of claim 1 , wherein the second housing member includes a third pressure opening and a wall defining a first chamber and a second chamber, wherein the first chamber is in fluid communication with the first pressure sensing die via the first opening in the substrate and the second chamber is in fluid communication with the first pressure sensing die via a second opening in the substrate.
9. The pressure sensor of claim 1 , further comprising a third pressure sensing die mounted on the first side of the substrate, wherein the third pressure sensing die includes a diaphragm and one or more piezoresistive elements positioned on the diaphragm.
10. The pressure sensor of claim 1 , further comprising:
a multiplexer electrically connected to an output of each of the first pressure sensing die and the second pressure sensing die, the multiplexer having an output; and
signal conditioning circuitry electrically connected to the output of the multiplexer.
11. A pressure sensor comprising:
a substrate;
a first pressure sensing die mounted on the substrate, wherein the first pressure sensing die includes a diaphragm and one or more piezoresistive elements positioned on the diaphragm;
a second pressure sensing die mounted on the substrate, wherein the second pressure sensing die includes a diaphragm and one or more piezoresistive elements positioned on the diaphragm;
a third pressure sensing die mounted on the substrate, wherein the third pressure sensing die includes a diaphragm and one or more piezoresistive elements positioned on the diaphragm;
a housing positioned on the substrate and defining one or more cavities around the first pressure sensing die, the second pressure sensing die, and the third pressure sensing die;
wherein the first pressure sensing die, the second pressure sensing die, and the third pressure sensing die are configured to sense different parameters and/or have different resolutions.
12. The pressure sensor of claim 11 , wherein at least one of the first pressure sensing die, the second pressure sensing die, and third pressure sensing die is a differential pressure sensor.
13. The pressure sensor of claim 11 , wherein at least one of the first pressure sensing die, the second pressure sensing die, and third pressure sensing die is a gauge pressure sensor.
14. The pressure sensor of claim 11 , wherein at least one of the first pressure sensing die, the second pressure sensing die, and third pressure sensing die is an absolute pressure sensor configured to sense barometric pressure.
15. A pressure sensor comprising:
a substrate including a first side and a second side;
a first pressure sensing die mounted on the first side of the substrate, wherein the first pressure sensing die includes a diaphragm and one or more piezoresistive elements positioned on the diaphragm, wherein the first pressure sensing die is positioned over a first opening in the substrate, the first opening extending between the first side and the second side of the substrate;
a second pressure sensing die mounted on the first side of the substrate, wherein the second pressure sensing die includes a diaphragm and one or more piezoresistive elements positioned on the diaphragm, wherein the second pressure sensing die is positioned over a second opening in the substrate, the second opening extending between the first side and the second side of the substrate; and
a first housing member positioned on the first side of the substrate and defining a first cavity around the first pressure sensing die and the second pressure sensing die.
16. The pressure sensor of claim 15 , further comprising a second housing member positioned on the second side of the substrate and defining a second cavity having a first chamber, wherein the second housing member includes a first pressure opening for exposing the first pressure sensing die to a first pressure via the first opening and a second pressure opening for exposing the second pressure sensing die to a second pressure via the second opening.
17. The pressure sensor of claim 16 , wherein a difference between the first pressure and the second pressure can be determined by a difference between an output signal of the first pressure sensing die and an output signal of the second pressure sensing die.
18. The pressure sensor of claim 17 , wherein the only a back-side of the pressure sensing diaphragm of each of the first pressure sensing die and the second pressure sensing die is exposed to the first pressure or the second pressure.
19. The pressure sensor of claim 15 , wherein the first pressure sensing die is configured to provide a first resolution of a sensed pressure over a first range and the second pressure sensing die is configured to provide a second resolution of the sensed pressure, wherein the first resolution is higher than the second resolution and the first range is narrower than the second range.
20. The pressure sensor of claim 15 , wherein the first pressure sensing die is a differential pressure sensing die exposed to a first and second pressure and the second pressure sensing die is a gauge pressure sensor exposed to the first pressure.